31616646641 has 4 divisors (see below), whose sum is σ = 31641406452. Its totient is φ = 31591886832.

The previous prime is 31616646619. The next prime is 31616646673. The reversal of 31616646641 is 14664661613.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 14664661613 = 7 ⋅2094951659.

It can be written as a sum of positive squares in 2 ways, for example, as 24584985616 + 7031661025 = 156796^2 + 83855^2 .

It is a cyclic number.

It is not a de Polignac number, because 31616646641 - 2⁶ = 31616646577 is a prime.

It is a super-2 number, since 2×31616646641² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 31616646592 and 31616646601.

It is not an unprimeable number, because it can be changed into a prime (31616646601) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12377990 + ... + 12380543.

It is an arithmetic number, because the mean of its divisors is an integer number (7910351613).

Almost surely, 2^31616646641 is an apocalyptic number.

It is an amenable number.

31616646641 is a deficient number, since it is larger than the sum of its proper divisors (24759811).

31616646641 is a wasteful number, since it uses less digits than its factorization.

31616646641 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24759810.

The product of its digits is 373248, while the sum is 44.

The spelling of 31616646641 in words is "thirty-one billion, six hundred sixteen million, six hundred forty-six thousand, six hundred forty-one".